diff options
Diffstat (limited to 'drivers/pwm/pwm-clps711x.c')
| -rw-r--r-- | drivers/pwm/pwm-clps711x.c | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/drivers/pwm/pwm-clps711x.c b/drivers/pwm/pwm-clps711x.c new file mode 100644 index 000000000000..2c92ce754872 --- /dev/null +++ b/drivers/pwm/pwm-clps711x.c @@ -0,0 +1,110 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Cirrus Logic CLPS711X PWM driver + * Author: Alexander Shiyan <shc_work@mail.ru> + */ + +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pwm.h> + +struct clps711x_chip { + void __iomem *pmpcon; + struct clk *clk; +}; + +static inline struct clps711x_chip *to_clps711x_chip(struct pwm_chip *chip) +{ + return pwmchip_get_drvdata(chip); +} + +static int clps711x_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct clps711x_chip *priv = to_clps711x_chip(chip); + unsigned int freq = clk_get_rate(priv->clk); + + if (!freq) + return -EINVAL; + + /* Store constant period value */ + pwm->args.period = DIV_ROUND_CLOSEST(NSEC_PER_SEC, freq); + + return 0; +} + +static int clps711x_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_state *state) +{ + struct clps711x_chip *priv = to_clps711x_chip(chip); + /* PWM0 - bits 4..7, PWM1 - bits 8..11 */ + u32 shift = (pwm->hwpwm + 1) * 4; + u32 pmpcon, val; + + if (state->polarity != PWM_POLARITY_NORMAL) + return -EINVAL; + + if (state->period != pwm->args.period) + return -EINVAL; + + if (state->enabled) + val = mul_u64_u64_div_u64(state->duty_cycle, 0xf, state->period); + else + val = 0; + + pmpcon = readl(priv->pmpcon); + pmpcon &= ~(0xf << shift); + pmpcon |= val << shift; + writel(pmpcon, priv->pmpcon); + + return 0; +} + +static const struct pwm_ops clps711x_pwm_ops = { + .request = clps711x_pwm_request, + .apply = clps711x_pwm_apply, +}; + +static int clps711x_pwm_probe(struct platform_device *pdev) +{ + struct pwm_chip *chip; + struct clps711x_chip *priv; + + chip = devm_pwmchip_alloc(&pdev->dev, 2, sizeof(*priv)); + if (IS_ERR(chip)) + return PTR_ERR(chip); + priv = to_clps711x_chip(chip); + + priv->pmpcon = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(priv->pmpcon)) + return PTR_ERR(priv->pmpcon); + + priv->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(priv->clk)) + return PTR_ERR(priv->clk); + + chip->ops = &clps711x_pwm_ops; + + return devm_pwmchip_add(&pdev->dev, chip); +} + +static const struct of_device_id clps711x_pwm_dt_ids[] = { + { .compatible = "cirrus,ep7209-pwm", }, + { } +}; +MODULE_DEVICE_TABLE(of, clps711x_pwm_dt_ids); + +static struct platform_driver clps711x_pwm_driver = { + .driver = { + .name = "clps711x-pwm", + .of_match_table = clps711x_pwm_dt_ids, + }, + .probe = clps711x_pwm_probe, +}; +module_platform_driver(clps711x_pwm_driver); + +MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>"); +MODULE_DESCRIPTION("Cirrus Logic CLPS711X PWM driver"); +MODULE_LICENSE("GPL"); |
